This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. This management study treats Yerkes'colonies of SIV-infected and uninfected sooty mangabeys (SMs) as cohorts for a biannual Immuno-virological evaluation. The biannual sample collections began in 2004 and between the years of 2004-2009 more than 500 peripheral blood samples were collected. A complete analysis has been conducted on these samples for measurement of viral load and 28 immunological parameters. This information, and the repository of plasma and PBMC frozen samples, are made available for selected research projects to both Yerkes and non-Yerkes investigators upon request. The samples utilized from this project have been instrumental to several important publications in the field, since this approach generated a large set of immunological and virological data to conduct as systematic longitudinal assessment of the animals'health status with specific focus on the course of SIV infection. Of note, the third survey of the animals was completed in 2009, and the relevant immunological and virological data were published in Taaffe et al., J Virol 2010. This set of data has also allowed the rapid and effective identification of SMs with specific immunological and or virological features, and to match against the completed SM colony pedigree.